“Star” in the West
Most people know that planets shine by reflected light from our Sun. Just how brightly they shine depends upon several factors, including their distance from us and from the Sun, their size, and how well they reflect the Sun’s light. The planet that checks these boxes the best is Venus, often called Earth’s sister planet because it is nearly the same size and relatively close by.
The current evening appearance of Venus has actually been under way for several months, but it hasn’t been very conspicuous. Like all the other planets and the Sun and Moon, Venus’ orbit is in the plane of our solar system. Its path across the sky is called the ecliptic. As seen from the northern hemisphere, the ecliptic is at a low angle to the horizon during summer and fall, causing Venus to seem to hover low in the western to southwestern sky and set soon after sunset. For many people, it has been hard to find due to trees and other landscape obstacles, but if you have been watching over the last few weeks, the situation has been steadily improving.
From December through February, Venus will set more than three hours after sunset and will blaze away as the brilliant “Evening Star” that so many of us remember, far outshining any other object except the Sun and Moon. Venus’ height above the horizon will remain more or less constant for the next few months if you look at about the same interval after sunset. The major change that will take place is that Venus will gradually shift to the right along the horizon, appearing in the southwest in December but north of west by February.
Each month, Venus will appear as a striking pair with the evening crescent moon. This will occur on the evenings of December 4th, January 3rd, and February & March 1st. This month’s view is shown below. This is a great photo opportunity with your cellphone- set it to “night shot” or similar setting, and experiment. If you can take a longer exposure, the outline of the unlit part of the Moon, known as earthshine, can be imaged. Sunlight reflects off the Moon on to the Earth and then back on to the Moon again, and it is striking as seen in binoculars and small telescopes. Mark your calendar- the planet Saturn will appear close to Venus around January 17, and there will be a nice pairing with Mercury during the first half of March, offering a great chance to find the sometimes elusive innermost planet.

Venus and the crescent Moon will appear in the southwestern sky on the evening of December 4th.
As we move into late winter, Venus will appear more and more between the Earth and Sun, and it will appear to first gradually and then rapidly drop towards the horizon, disappearing into the dusk during the second half of March. Usually appearing as a brilliant featureless ball in a telescope, Venus at this time will appear as a spectacular thin crescent. This dramatic exit from the night sky will definitely be discussed in later editions of this blog.
The Gateway to the Stars program will resume next spring, with a schedule of Astronomy or National Park related programs that precede telescope viewing held on the Entrance Plaza. The first program is tentatively set for May 10, 2025.